Source: "The DiSC® Indra® Research Report," published by Inscape Publishing, 2003
DiSC® has a long history and the publisher, Wiley, continually works to make it more reliable, easier to administer and more memorable for the user.
DiSC theory and William Moulton Marston
The DiSC Model of Behavior was first proposed by William Moulton Marston, a physiological psychologist with a Ph.D. from Harvard. His 1928 book, Emotions of Normal People, explains his theory on how normal human emotions lead to behavioral differences among groups of people and how a person's behavior might change over time. His work focused on directly observable and measurable psychological phenomena. He was interested in using practical explanations to help people understand and manage their experiences and relationships.
Marston theorized that the behavioral expression of emotions could be categorized into four primary types, stemming from the person's perceptions of self in relationship to his or her environment. These four types were labeled by Marston as Dominance (D), Inducement (I), Submission (S), and Compliance (C).
From theory to assessment
Walter V. Clarke, an industrial psychologist, was the first person to build an assessment instrument (personality profile test) using Marston's theories, even though that was not initially his intent. In 1956 he published the Activity Vector Analysis, a checklist of adjectives on which he asked people to mark descriptors they identified as true of themselves. The tool, used by Clarke since 1948, was intended for personnel selection by businesses. The four factors in his data (aggressive, sociable, stable and avoidant) were based on Marston's model.
About 10 years later, Walter Clarke Associates developed a new version of this instrument for John Cleaver. It was called Self Discription. Instead of using a checklist, this test forced respondents to make a choice between two or more terms. Factor analysis of this assessment added to the support of a DISC-based instrument.
The Personal Profile System® (PPS)
Self Discription was used by John Geier, Ph.D., to create the original Personal Profile System® (PPS) in the 1970s. Through hundreds of clinical interviews, he furthered the understanding of the 15 basic patterns discovered by Clarke.
Inscape Publishing improved this instrument's reliability by adding new items and removing non-functioning items. The new assessment was named the Personal Profile System 2800 Series (PPS 2800) and was first published in 1994. It was primarily used for increasing self-awareness in a setting where an individual could use the insights in their interactions with others. This self-scored and self-interpreted assessment is now known as DiSC® Classic.
In 2003 Inscape took DiSC Classic a step further by launching DiSC® Classic 2.0, an online version of the paper profile that includes a richer narrative feedback.
DiSC® Classic to Everything DiSC®
The Everything DiSC® product family, launched by Inscape Publishing in 2007, was created to make the DiSC assessment even more valuable to its users. It introduced more highly personalized reports, customizable facilitation tools and electronic access to unlimited follow-up reports.
The most visible change is to the reports: they no longer showed a graph, but instead now show a person's tendencies within a circle. Information is presented much more visibly, intuitively and memorably this way. This representation allows participants to quickly understand relationships in the DiSC model and recognize patterns within group dynamics.
For more information see
How My Graph Became a Dot - Adaptive Testing
Everything DiSC Research Validation Study - Research on the Everything DiSC profiles for Management, Sales, Workplace, and Comparison Reports
Newest DiSC products and updates
In a continuing effort to make DiSC a more valid and reliable instrument, all Everything DiSC questionnaires were updated in 2013 to a computerized adaptive testing format. Adaptive testing showed a 35 percent improvement of reliability scale for people who respond inconsistently, a 12 percent increase in accuracy over the 79-item assessment (previously used with Everything DiSC profiles), and a 32 percent increase in accuracy over DiSC Classic.
MyEverythingDisc.com is the newest tool created to make DiSC more easily accessible. Users can view and share their own profiles, create Comparison Reports, and learn more about the history behind DiSC.
Based on best practices and four years of development effort, Everything DiSC Work of Leaders is the most researched Everything DiSC assessment. With it, you can discover your DiSC leadership style and learn a simple three-step process to help you approach the fundamental work of leaders: Vision, Alignment and Execution.
Everything DiSC 363™ for Leaders combines the best of traditional multi-rater 360s with the simplicity and power of DiSC. It pulls together qualitative and quantitative data from a 72-item leadership assessment and a 79-item Everything DiSC assessment to give leaders an accurate picture of their performance in the interpersonal realm of leadership. In the Everything DiSC Leadership model, each of the eight leadership approaches corresponds to a DiSC scale.
The Everything DiSC assessment has also been included in The Five Behaviors of a Cohesive Team™ profile to help teams understand how to apply The Five Behaviors™ model of Trust, Conflict, Commitment, Accountability, and Results to their work culture.